This invention relates to a disposable pull-on diaper provided with tape fasteners used to fasten the diaper in a rolled up state for disposal.
Japanese Patent Application Publication Nos. 1997-253123A and 1997-253124A describe disposable pull-on diapers of a type comprising a liquid-pervious topsheet, a liquid-impervious backsheet and a liquid-absorbent core disposed between these two sheets so as to configure front and rear waist regions and a crotch region positioned between these waist regions wherein, in the rear waist region, a tape fastener or tape fasteners is (are) attached to the outer surface of the backsheet so that the diaper may be fastened in a rolled up state for disposal after use.
In the diaper described in Japanese Patent Application Publication No. 1997-253123A, a tape fastener is formed by a single tape strip extending in a waist-surrounding direction and having a central portion bonded to the diaper. The remaining right and left side portions of the tape strip are folded up so that these portions may be unfolded rightward and leftward in the waist-surrounding direction. The right and left side portions are provided with bonding zones so as to maintain the folded up state of the diaper.
In the diaper described in Japanese Patent Application Publication No. 1997-253124A, tape fasteners are formed by a pair of strips of adhesive tape extending in parallel to each other in the waist-surrounding direction and spaced apart from each other in the longitudinal direction of the diaper.
For disposal, each of the diapers disclosed in the Publications is rolled from opposite side portions thereof, in a transverse direction, inward and toward the tape fastener(s), and then the tape fastener(s) is/are wound around the diaper and anchored on the outer surface of the backsheet by pressure-sensitive adhesive. The rolled up diaper is fastened by the tape fastener(s) in this manner and remains in the rolled up state.
The diaper disclosed in the Publications requires the user to roll up the diaper from both side portions inward and toward the tape fastener(s), and then wind the tape fastener(s) around the rolled up diaper. Therefor time and labor are required for the operations of rolling up the diaper and winding the tape fastener(s) around this rolled up diaper. In addition, it is impossible to close the waist-opening of the known diaper and there is always anxiety that excretion and/or its odor might leak from the waist-opening.
It is an object of this invention to provide a disposable pull-on diaper adapted to be easily rolled up and maintained in the rolled up state for disposal after use without any apprehension that excretion and/or its odor might leak from the waist-opening and the pair of leg-openings.
According to this invention, there is provided a disposable pull-on diaper comprising a diaper structure having front and rear waist regions opposed to each other and a crotch region positioned between these waist regions. The front and rear waist regions are connected together in the vicinity of transversely opposite side edge portions thereof to define a waist-opening and a pair of leg-openings. A pair of tape fasteners adapted to fasten the diaper in a rolled up state are attached to the outer surface of the diaper structure and anchoring means or elements are formed on inner surfaces of the tape fasteners facing the outer surface of the diaper structure.
The tape fasteners are provided in the vicinity of the transversely opposite side edge portions in one of the front and rear waist regions so as to extend in a longitudinal direction wherein each of the tape fasteners has an upper end portion lying adjacent the waist-opening and lower end portion lying adjacent the leg-openings. The lower end portions are bonded to the diaper structure by bonding zones extending in a waist-surrounding direction in the vicinity of respective peripheral edges of the leg-openings wherein the bonding zones extend obliquely inward in the waist-surrounding direction from the transversely opposite side edge portions toward the upper end portions.
According to one preferred embodiment of this invention, the lower end portions of the tape fasteners are positioned more inwardly in the waist-surrounding direction than the respective upper end portions of the tape fasteners. Each of the tape fasteners obliquely extends from its lower end portion toward its upper end portion so as to be gradually spaced further away from the other tape fastener.
According to another preferred embodiment of this invention, elastically stretchable members associated with the leg-openings are provided to extend in the leg-surrounding directions. The members are attached under extension to peripheral edge portions of the leg-openings and the bonding zones overlap at least partially the elastically stretchable members associated with the leg-openings.
According to still another preferred embodiment of this invention, the anchoring means or elements are formed by one of pressure-sensitive adhesive agents applied on the tape fasteners and hook members attached to the tape fasteners. Release sheets adapted to temporarily retain the tape fasteners are attached to the outer surface of the diaper structure in the vicinity of the transversely opposite side edge portions.